Users are increasingly performing tasks using remote computing resources, often referred to as part of “the cloud.” This has many advantages, as users do not have to purchase and maintain dedicated hardware and software, and instead can pay for only those resources that are needed at any given time, where those resources typically will be managed by a resource or “cloud” provider. It will often be the case that a user will want one or more cloud resources to perform actions on behalf of the user. At least some of these actions may require some verification that the resource is authorized to perform such a task or action on behalf of the user and/or that the user is authorized to perform such a task or action. For example, a user might want messages sent that are associated with a particular email address, or actions performed with respect to a particular domain name. There is currently no standardized way for the cloud resources to verify that the user is associated with the corresponding domains or addresses, and authorized to have actions performed for them.